Shutter-governor assembly for motion-picture apparatus



Sept. 15, 1953 wn- 2,651,965

SHUTTER-GOVERNOR ASSEMBLY FOR MOTION-PICTURE APPARATUS Filed Feb. 10, 1951 2 Sheets-Sheet l F1G.l.

53 45- Q r'y36 3 FIGS.

31 C) OTTO WITTEL J9 O INVENTOR J- 9 35 g 5417 oziNEY a? AGENT Q. WITTEL,

Sept. 15, 1953 2 Sheets-Sheet 2 Filed Feb. 10, 1951 m m mm mm m w w gum 0 T m T F O 1 m 5 m m 3 5 m 8 m an a v Z w 6 5 G 6 I Patented Sept. 15, 1953 SHUTTER-GOVEBN OR ASSEMBLY FOR MOTION-PICTURE APPARATUS Otto Wittel, Rochester,

man Kodak Company,

poration of New Jersey Application February 10, 1951, Serial N 0. 210,325

6 Claims.

This invention relates to motion picture apparatus and more particularly to a combined speed control device and shutter therefor and to a. method of balancing and truing such a control device.

As is well known, motion picture apparatus and particularly motion picture cameras are operated at a. standard speed. To maintain a uniform speed of the film-advancing mechanism, which is usually driven by a spring motor, a governor is connected to the mechanism to insure maintenance of the desired uniform speed. In the present invention, a governor and shutter are combined into a single unit or assembly and rotatably mounted in a recess in front of the film plane. The shutter-governor is provided with resilient arms which are flexed outwardly upon rotation of the assembly so that the peripheral surfaces of the arms will en'g'age a friction material lining the wall of the recess to control the peed of the film advancing mechanism. Since the shutter-governor assembly is a single unit, it can very readily be balanced and the peripheral surfaces of the arms can be reduced or trued to the diameter of the trolling speed.

The primary object of the invention, therefore, is to provide a speed control device and shutter for motion picture apparatus in which the two devices are combined to provide a single compact assembly.

Another object of the invention is to provide a shutter-governor assembly for motion picture apparatus in which the assembly is mounted within a cylindrical recess and the peripheral surfaces of the resilient arms of the assembly engage the walls of the recess to control the speed of the film-advancing mechanism.

Yet another object ofthe invention is to provide a shutter-governor assembly for motion picture apparatus in -whic'h circular segmental welghtsare secured-toeach of the two resilient arms of the assembly, one-of the weights being provided with a shutter opening; and which cause the arms to flex outwardly when the assembly is rotated so that the peripheral surfaces of the arms engage the walls of the recess in which said assembly is mounted for controlling the speed of the film-advancing mechanism.

And another object of theinvention is to provlde a method by which the shutter-governor assembly is balanced and the peripheral surfaces of the resilient arms of said assembly are reduced to a predetermined diameter to insure proper functioning of the assembly at the desired and recess which defines the con- 2 N. Y., assignor to East- Rochester, Y., a corpredetermined speed when paratus. I

These and other objects and advantages will be apparent to those skilled in the art by the description which follows.

The objects of the invention are embodied in a shutter-governor assembly for motion picture cameras. In the illustrated embodiment of the invention, the camera is provided with a mechanism supporting frame having a cylindrical recess and an aperture aligned with the lens or objective. The shutter-governor assembly is rotatably mounted within the recess and operatively connected to the film-advancing mechanism. The shutter-governor assembly comprises 2. diametrical cross bar having arcuate resilient arms integral with opposite ends of said bar and extending in opposite directions therefrom. A circular segmental weight is secured to each of said arms, one of said weights being provided with a shutter opening adapted to be aligned with the aperture in the supporting frame. Upon rotation of the assembly, the weights, due to centrifugal force, flex the arms outwardly thereby causing the peripheral surfaces of the arms to engage a friction material lining the wall of said recess to control the speed of the advancing mechanism.

Reference is now made to the accompanying drawings wherein like reference numerals designat like parts and wherein:

Fig. 1 is a side elevation of a camera embodying the invention Fig. 2 is a rear view of the shutter-governor assembly and showing the arms in their normal position with respect to the diameter at which said arms function to control the drive mechanism;

Fig. 3 is a front elevation of the shutter-governor assembly positioned in the recess and showing the arms in their controlling position in which position the arms are in engagement with a friction material lining the wall of the recess;

Fig. 4 is a sectional view taken substantially on the line 4-1 of Fig. 3;

Fig. 5 is a horizontal section through an arrangement of elements for mounting, rotating and clamping the shutter-governor assembly to balance the assembly and reduce and/or true the peripheral surfaces of the arms to a predetermined diameter;

Fig. 6 is a perspective view of the driving sleeve and shutter-governor assembly and showing the drive pin for engaging the diametrical cross bar to rotate the assembly;

assembled in the apmotion picture 1 is a front elevation of the driving sleeve and showing the relative position of the drivin pin and the recesses therein and the two engaging surfaces forming the face thereof; and.

Fig. 8 is a partial sectional view taken on line 88 of Fig. '1 and showing the relation of the depth of the slot in the driving pin to the offset surfaces forming the face of the driving sleeve.

In the illustrated embodiment of the invention, the camera I!) is of the type designed for use in the hand. Such a camera comprises a casing provided with a suitable objective contained in mount l2 and a finder comprising front element l3 and rear element M. The side cover I5 is removable to permit access to the film chamber and the other side is provided with a similar cover to permit access to the mechanism which is separated from the film chamber by plate It, as shown in Fig. 4. The forward end of the camera carries a mechanism supporting frame l1 for supporting the film gate I8, the shutter-governor assembly IS, the film-advancing claw 23, the

shutter release mechanism, etc., as is well known in the art. The frame I1 is also provided with recess 2| and aperture 22 into which mount l2 extends.

The film-advancing means, as shown in Fig. 4, comprises a spring motor 25 which drives gear 26 secured integral with the crown gear 21 by .means of gear 28, both of said gears 25 and 21 ,being rotatably mounted on shaft 29.

Gear 21 meshes with pinion 30 secured to and forming a part of the shutter-governor assembly IE! together with eccentric 3|. Film-advancing claw 20 is provided with an elongated aperture which engages eccentric 3|, is pivotally mounted on frame H at 32, and has a film-engaging portion 33 extending through an aperture in film gate IS in a well-known manner.

The structure described thus far is equivalent to that found in most motion picture cameras and is illustrative of one type of mechanism to which the invention may be applied for control purposes.

The shutter-governor assembly I9 comprises a diametrical cross bar 35 having an enlarged center portion 36 which has a notch 31 therein for arresting the assembly upon movement of release button 38 in an upward direction to move lug 34 into the path of sad notch, as shown in Fig. 2. A thin and circular hardened plate 39 has a notch 31 congruent in shape to notch 31 in portion 36 and is secured thereunder, as shown in Fig. 4, to prevent lug 34 from deforming notch 31 as it abuts thereagainst. Plate 39, cross bar 35, and eccentric 3| are provided with suitable apertures to receive shank 4!) of pinion 3B and are maintained in position thereon between the underside of the teeth of said pinion and the formed over end of shank 4D. Pinion 30 is provided with aperture 4| to receive shaft 42 anchored in frame I1 and is maintained thereon by spring washer 43 which engages groove 44 in the end of shaft 42. At opposite ends of bar 35 arms 45 and 46 extend in opposite directions, said arms comprising resilient portions 41 and 4B, respectively, which are integral with cross bar 35 at one end thereof and integral at the other end with weight-supporting portions 49 and 50, respectively, the portions 49 and 50 terminating near opposite ends of bar 35. As will be noted from Fig. 2, the peripheral surfaces 5| and 52 of arms 45 and 45, respectively, are substantially semicircular about centers 0' and 0, respectively, said centers not being coincident with the center of rotation O of the assembly when the assembly is in its normal or arrested position. Secured to portions 49 and 50 by rivets 53 are weights 54 and 55 which are circular segments relieved at the center to provide clearance around the eccentric 3| and which have an outer radius 1* about centers 0 and O" which is smaller than radius r of arms 45 and 46. Weight 55 is provided with shutter aperture 5'5 which, upon rotation of assembly I9, is aligned with aperture 22 in frame l1 and aperture 51 in film gate l8. Since weight 55 is provided with a relatively large aperture, this weight is thicker than weight 54 to compensate for the aperture.

Before making an exposure, the spring motor 25 is wound or tensioned by a handle not shown and is prevented from advancing film by lug 34 in the path of notch 31. When release button 38 is moved vertically downward, lug 34 is moved out of the path of notch 31 and motor 25 through gears 28, 26, and 21 drives pinion 4|) in a clockwise direction, as viewed from Fig. 3. The eccentric 3|, therefore, oscillates claw 20 to intermittently advance the film strip past aperture 51, and aperture 56 is rotated past aperture 51 to permit exposure of the film strip. It is understood, of course, that the position of eccentric lit with respect to aperture 55 is such that the film strip is stationary during the movement of aperture 56 past aperture 51. As the speed of assembly I!) increases, the centrifugal force acting on weights 54 and 55 will cause resilient portions 41 and 48 to flex, thereby causing arms 45 and 45 to move outwardly toward recess 2|. At the normal operating speed of the film-advancing mechanism, the peripheral surfaces 5| and 52 of the arms 45 and 46 will engage the walls of re- 0655 2| and prevent spring motor 25 from driving the mechanism at a higher speed. When this condition is attained, the centers 0, O and 0" will coincide, as shown in Fig. 3. To prevent excessive wear, more positive braking action and quiet operation, a strip of friction or braking material BI] is placed within recess 2| and against the wall thereof, as shown in Figs. 3 and 4. Such a friction material may be of cork, leather or a plastic material. In the present instance, it was found that a. strip of cellulose acetate film base provided the best results. The radius 1*, when such a material is used, should be equal to the distance from the center 0 to the inside surface of the braking strip 50, as indicated by the broken line in Fig. 2.

The shutter-governor assembly just described lends itself very readily to a simple method of balancing said assembly and, at the same time, truing peripheral surfaces 5| and 52 of arms 45 and 46 to insure proper engagement of said surfaces with brake lining 60 or the wall of recess 2|. In Figs. 5-8 one form of apparatus is disclosed for the balancing and truing of the shutter-governor assembly hereinbefore described. Chuck plate is screwed onto the spindle of a lathe or some other driving device which can be rotated at the controlling speed at which the assembly I9 is to function. Secured to plate 65 by screws 56 is a mounting plate 61 to which the driving plate 68 is secured by screws 69. Plate 61 carries a spindle 10 which extends through a suitable aperture in plate 68 for receiving assembly l9, and plate 68 is provided with a recess 1| for pinion 30 and eccentric 3| and with recesses 12 for receiving the heads of rivets 53. Secured to plate 68 is the driving pin 13 which is positioned thereon to extend through aperture 56 of assembly l9 and engage aperture 15 .74 in clamping sleeve 15.. Since weights 54 and 5,5 are of different thicknesses, the face 1-6 :of plate '68 comprises two surfaces, a surface 11 which engages weight 55 and asurface 18 which is above surface Ill and which engages weight 54, as shown in Fig, 8. Clamping sleeve 15 is rotatably mounted within sleeve 18 by means of bearing Eli and ball bearing .84, bearingtl being retained in position .by ring 82 is integral with .the tapered shank ,83 mounted inthe tail-- stock 84 ,of the lathe, 'Recesses 85 are provided in the face of sleeve 7! to receive the turned over ends of rivets 53.

To balanoeand true assembly 19, the assembly t8 outwardly and to insure engagement of cross bar .35 by pin .13, pin 73 is provided with notch 36, see Fig. 8. After the assembly IQgha-s been properly positioned on spindle l0, tail-stock 84 is moved toward the assembly with aperture 14 of sleeve 15 aligned for receiving .pin 13 and the recesses 85 ali ned for receiving rivet 53 and is stopped in a position in which the face of sleeve 75 is spaced from assembly I9 by a very small amount. Chuck plate 65, plate 61 and driving plate 68 are then rotated at a speed equivalent to the controlling speed of assembly IS, the rotary motion of these parts being transmitted to assembly l9 and clamping sleeve '15 by driving pin 73. When the arms 4'! and are in their extended or controlling position, the tail-stock 84 4 is moved axially so that the face of sleeve 75 engages cross bar 35, the weight supporting portions 49 and 5t and the arms 41 and 48 to clamp these parts together with weights 54 and 55 against surfaces 1? and 18 of plate 68; Sleeve E8, assembly I9, and sleeve 75 will then be mtated as a unit and at the controlling speed. A cutting tool is then moved radially toward the moving peripheral surfaces 51 and 52 of arms 47 and 48 and the excess of material between said tool and the predetermined diameter ofsaid surfaces is removed, thereby insuring that said surfaces will uniformly engage the brake lining at the controlling speed when assembled in the camera.

In instances when one arm or weight is slightly heavier than the other, that arm will flex outwardly farther than the other and necessitate removal of more material, thereby insuring that the assembly is balanced. On the other hand, if the cutting tool is moved radially to the predetermined diameter and neither arm is contacted by the tool, such an assembly can be readily rejected, since it will not function to control at the predetermined speed. While reference has been made to moving a cutting tool toward the assembly, it is to be understood that truing of said peripheral surfaces may be accomplished by cutting, grinding, filing or in any other manner Once the excess of material over the predetermined diameter has been determined.

While the present invention has been disclosed and described in detail with respect to controlling motion picture film apparatus, it will be apparent to those skilled in the art that the invention may be applied to other apparatus without depart- Ling tron-1 the invention, the scope of which is clu'ding a diametrical cross bar having resilient :arci-iate integral therewith and extending S cm each end thereof in opposite directions, and circular segmental members secured to each of said arms, one of said members being provided with a shutter --opening adapted to be aligned "with said aperture for intermittently exposing film strip to the light entering said aperted upon rotation of said assembly "to flex said arms outwardly whereby the peripheral surfaces of said arms engage said recess to control the speed of said advancing means.

In motion picture apparatus having a mechanism sup" orting frame provided with an aperture zlindrical recess, said aperturebeing within the circular area defined by said recess and in the bottom wall thereof, the combination comprising means for advancing a film strip past said aperture, and a shutter-governor assembly rotatably mounted within said recess and op- 'er-aticvcl connected to said advancing means and including a :diainetrical cross bar having resilient arcuate arms integral therewith and extending from each end thereof in opposite directions, said arms being 'adapted'to be flexed from a normal position to a position in which the peripheral surfaces thereof form circular arcs having a raidius substantially equal to that of said recess, and circular segmental members secured to each of arms, one of said members being provided with an arcuate shutter opening adapted to be aligned with said aperture for intermittently exposing said film strip to the light entering said aperture, and adapted upon rotation of said assembly to flex said arms outwardly whereby said peripheral surfaces engage said recess to control the speed of said advancing means.

3. In motion picture apparatus having a mechanism supporting frame provided with an aperture and a cylindrical recess, said aperture being within the circular area defined by said recess and in the bottom wall thereof, the combination comprising means for advancing a film strip past said aperture, and a shutter-governor assembly rotatably mounted within said recess and operatively connected to said advancing means and including a diametrical cross bar having resilient arms, said arms having free ends spaced from said bar and the other ends of said arms integral with said bar at opposite ends thereof and each arm having its peripheral surface formed substantially semi-circular about a center other than the center of rotation of said assembly, and circular segmental members secured to each of said arms, one of said members being provided with an arcuate shutter opening adapted to be aligned with said aperture for intermittently exposing said film strip to the light entering said aperture, and adapted upon rotation of said assembly to flex said arms outwardly whereby the centers of said peripheral surfaces coincide with the center of rotation of said assembly and said p p eral surfaces engage said recess to control the speed of said advancing means. i

4. In motion picture apparatus having a mechanism supporting frame provided with an aperture and a cylindrical recess, said aperture being within the circular area defined by said recess and in the bottom wall thereof, the combination comprising means for advancing a film strip past said aperture, and a shutter-governor assembly rotatably mounted within said recess and operatively connected to said advancing means and including a diametrical cross bar having weight supporting members on opposite sides thereof and resilient arm's integral with one end of said weight supporting members and opposite ends of said bar, said arms and members having continuous peripheral surfaces formed substantially semicircular about centers other than the center of rotation of said assembly, and a circular segmental weight secured to each of said weight supporting members, one of said weights being provided with an arcuate shutter opening adapted to be aligned with said aperture for intermittently exposing said film strip to the light entering said aperture, and adapted upon rotation of said assembly to flex said resilient arms outwardly whereby the centers of said peripheral surfaces coincide with the center of rotation of said assembly and said peripheral surfaces engage said recess to control the speed of said advancing means.

5. In motion picture apparatus having a mechanism supporting frame provided with an aperture and a cylindrical recess, said aperture being within the circular area defined by said recess and in the bottom wall thereof, the combination comprising means for advancing a film strip past said aperture, a friction material within said recess for providing a brake lining around the wall of said recess, and a shutter-governor assembly rotatably mounted within said recess and operatively connected to said advancing means and including a diametrical cross bar having resilient arcuate arms integral therewith and extending from each end thereof in opposite directions, and circular segmental weights secured to each of said arms, one of said weights being provided with an arcuate shutter opening adapted to be aligned with said aperture for intermittently exposing said film strip to the light entering said aperture, and adapted upon rotation of said assembly to flex said arms outwardly whereby the peripheral surfaces of said arms engage said friction material to control the speed of said advancing means.

6.. In motion picture apparatus having a mechanism supporting frame provided with an aperture and a cylindrical recess, said aperture being within the circular area defined by said recess and in the bottom wall thereof, the combination comprising means for advancing a film strip past said aperture, a strip of thermoplastic material within said recess for providing a brake lining around the wall thereof, and a shutter-governor assembly rotatably mounted within said recess and operatively connected to said advancing means and including a diametrical cross bar having resilient arms, said arms having free arms spaced from said bar and the other ends of said arms integral with said bar at opposite ends thereof and each arm having its peripheral surface formed substantially semi-circular about a center other than the center of rotation of said assembly, and circular segmental weights secured to each of said arms, one of said weights being provided with an arcuate exposure aperture adapted to be aligned with said aperture for intermittently exposing said film strip to the light entering said aperture, and adapted upon rotation of said assembly to flex said arms outwardly whereby the centers of said peripheral surfaces coincide with the center of rotation of said assembly and said peripheral surfaces engage said brake lining to control the speed of said advancmg means.

OTTO WITTEL.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,326,409 McMillan Dec. 30, 1919 1,518,562 Claybourn Dec. 9, 1924 1,544,521 Sosa June 30, 1925 1,661,741 Tierney Mar. 6', 1928 1,830,567 Shapiro Nov. 3, 1931 2,327,606 Saltz Aug. 24, 1943 2,376,302 Widmer g May 15, 1945 FOREIGN PATENTS Number Country Date 344,513 Great Britain Mar. 9, 1931 

